Black and white photo of Evertop computer on desk

The Evertop: A Low-Power, Off-Grid Solar Gem

April 23, 2025 by Heidi Ulrich 30 Comments

When was the last time you saw a computer actually outlast your weekend trip – and then some? Enter the Evertop, a portable IBM XT emulator powered by an ESP32 that doesn’t just flirt with low power; it basically lives off the grid. Designed by [ericjenott], hacker with a love for old-school computing and survivalist flair, this machine emulates 1980s PCs, runs DOS, Windows 3.0, and even MINIX, and stays powered for hundreds of hours. It has a built-in solar panel and 20,000mAh of battery, basically making it an old-school dream in a new-school shell.

What makes this build truly outstanding – besides the specs – is how it survives with no access to external power. It sports a 5.83-inch e-ink display that consumes zilch when static, hardware switches to cut off unused peripherals (because why waste power on a serial port you’re not using?), and a solar panel that pulls 700mA in full sun. And you guessed it – yes, it can hibernate to disk and resume where you left off. The Evertop is a tribute to 1980s computing, and a serious tool to gain some traction at remote hacker camps.

For the full breakdown, the original post has everything from firmware details to hibernation circuitry. Whether you’re a retro purist or an off-grid prepper, the Evertop deserves a place on your bench. Check out [ericjenott]’s project on Github here.

Solar-Powered E-Reader With No Buttons

March 10, 2025 by Bryan Cockfield 19 Comments

Modern e-readers such as the Amazon Kindle are incredible pieces of engineering, but that doesn’t mean there’s no room for improvement. A device custom-built to your own specifications is always going to provide a more satisfying experience than something purchased off the shelf. That’s why [fel88] put together this custom e-reader which offers a number of unique features, such as a solar panel on the back and button-free operation.

One issue with modern e-readers, at least as [fel88] sees it, is that they have a lot of unnecessary features. This project removes most of them, stripping down the device to its core functionality: a straightforward menu for selecting books and gesture-sensing for navigating the menu as well as changing the pages. The only physical input on the device is a small reed switch to turn the device on. A 3D printed case holds the e-ink display and encloses the inner workings, driven by an Arduino Mega 2560 and powered by three lithium-ion capacitors (LICs) and a small solar panel.

By dropping all of the unnecessary features, the device doesn’t need to waste energy with things like WiFi or Bluetooth and can get around 880 pages on a single charge, not counting any extra energy coming in through the solar panel while it’s operating. The LICs will also theoretically improve its life cycle as well. If you’re still stuck with a paperweight when you formerly had a working e-reader, though, there are plenty of ways to bring old devices back to life as well.

Hackaday Links: January 5, 2025

January 5, 2025 by Dan Maloney 4 Comments

Good news this week from the Sun’s far side as the Parker Solar Probe checked in after its speedrun through our star’s corona. Parker became the fastest human-made object ever — aside from the manhole cover, of course — as it fell into the Sun’s gravity well on Christmas Eve to pass within 6.1 million kilometers of the surface, in an attempt to study the extremely dynamic environment of the solar atmosphere. Similar to how manned spacecraft returning to Earth are blacked out from radio communications, the plasma soup Parker flew through meant everything it would do during the pass had to be autonomous, and we wouldn’t know how it went until the probe cleared the high-energy zone. The probe pinged Earth with a quick “I’m OK” message on December 26, and checked in with the Deep Space Network as scheduled on January 1, dumping telemetry data that indicated the spacecraft not only survived its brush with the corona but that every instrument performed as expected during the pass. The scientific data from the instruments won’t be downloaded until the probe is in a little better position, and then Parker will get to do the whole thing again twice more in 2025. Continue reading “Hackaday Links: January 5, 2025” →

Hackaday Links: December 22, 2024

December 22, 2024 by Dan Maloney 11 Comments

Early Monday morning, while many of us will be putting the finishing touches — or just beginning, ahem — on our Christmas preparations, solar scientists will hold their collective breath as they wait for word from the Parker Solar Probe’s record-setting passage through the sun’s atmosphere. The probe, which has been in a highly elliptical solar orbit since its 2018 launch, has been getting occasional gravitational nudges by close encounters with Venus. This has moved the perihelion ever closer to the sun’s surface, and on Monday morning it will make its closest approach yet, a mere 6.1 million kilometers from the roiling photosphere. That will put it inside the corona, the sun’s extremely energetic atmosphere, which we normally only see during total eclipses. Traveling at almost 700,000 kilometers per hour, it won’t be there very long, and it’ll be doing everything it needs to do autonomously since the high-energy plasma of the corona and the eight-light-minute distance makes remote control impossible. It’ll be a few days before communications are re-established and the data downloaded, which will make a nice present for the solar science community to unwrap.

Continue reading “Hackaday Links: December 22, 2024” →

Catching The View From The Edge Of Space

December 18, 2024 by Dan Maloney 26 Comments

Does “Pix or it didn’t happen” apply to traveling to the edge of space on a balloon-lofted solar observatory? Yes, it absolutely does.

The breathtaking views on this page come courtesy of IRIS-2, a compact imaging package that creators [Ramón García], [Miguel Angel Gomez], [David Mayo], and [Aitor Conde] recently decided to release as open source hardware. It rode to the edge of space aboard Sunrise III, a balloon-borne solar observatory designed to study solar magnetic fields and atmospheric plasma flows.

Continue reading “Catching The View From The Edge Of Space” →

Building Experience And Circuits For Lithium Capacitors

December 2, 2024 by Bryan Cockfield 22 Comments

For the cautious, a good piece of advice is to always wait to buy a new product until after the first model year, whether its cars or consumer electronics or any other major purchase. This gives the manufacturer a year to iron out the kinks and get everything ship shape the second time around. But not everyone is willing to wait on new tech. [Berto] has been interested in lithium capacitors, a fairly new type of super capacitor, and being unwilling to wait on support circuitry schematics to magically show up on the Internet he set about making his own.

The circuit he’s building here is a solar charger for the super capacitor. Being a fairly small device there’s not a lot of current, voltage, or energy, but these are different enough from other types of energy storage devices that it was worth taking a close look and designing something custom. An HT7533 is used for voltage regulation with a Schottky diode preventing return current to the solar cell, and a DW01 circuit is used to make sure that the capacitor doesn’t overcharge.

While the DW01 is made specifically for lithium ion batteries, [Berto] found that it was fairly suitable for this new type of capacitor as well. The capacitor itself is suited for many low-power, embedded applications where a battery might add complexity. Capacitors like this can charge much more rapidly and behave generally more linearly than their chemical cousins, and they aren’t limited to small applications either. For example, this RC plane was converted to run with super capacitors.

Senoko natural gas and oil-fired power station, Singapore in 2007. (Credit: Terence Ong)

Singapore’s 4300 Km Undersea Transmission Line With Australia Clears Regulatory Hurdle

October 23, 2024 by Maya Posch 22 Comments

The proposed AAPowerLink transmission line between Darwin (Australia) and Singapore. (Credit: Sun Cable)

Recently Singapore’s Energy Market Authority (EMA) granted Sun Cable conditional approval for its transmission line with Australia. Singapore has been faced for years now with the dilemma that its population’s energy needs keep increasing year-over-year, while it has very little space to build out its energy-producing infrastructure, least of all renewables with their massive footprints. This has left Singapore virtually completely dependent on natural gas-burning thermal plants. Continue reading “Singapore’s 4300 Km Undersea Transmission Line With Australia Clears Regulatory Hurdle” →